Which of the following is NOT a sign of tension pneumothorax?

• A. Unilateral absence of breath sounds
• B. Tracheal deviation away from the injured side
• C. Neck vein distention
• D. Bilateral breath sounds

Answer: (D)

Tension pneumothorax is a life-threatening condition in which air trapped in the pleural space builds pressure, collapsing the affected lung and shifting the mediastinum. This pressure disrupts venous return to the heart, so you see signs that reflect a unilateral problem: the side of injury typically has markedly reduced or absent breath sounds, neck veins become distended from impaired venous return, and the trachea may shift away from the injured side due to mediastinal compression. Hearing breath sounds on both sides argues against a tension pneumothorax because the major airflow obstruction and mediastinal shift are unilateral effects; bilateral breath sounds suggest the lungs are both being ventilated and the tension physiology is not present. In that scenario, you’d consider other injuries or processes, but not tension pneumothorax.